The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
There are many applications where a seal is required between a rotating component and a stationary component, such as in a transmission or an engine. Typically, a ring seal is used to seal the rotating component to the stationary component in order to keep fluids on either side of the ring seal from escaping to the other side. The ring seal typically includes a circular member that fits around the stationary component and an outer surface that engages the surface of the rotating component. One complication of the above described ring seal is that the ring seal must remain stationary relative to the rotating component while still maintaining an effective seal to the rotating component. In this regard, the typical ring seal must keep friction forces between the ring seal and the rotating component to a minimum while still maintaining enough radial force to keep fluid from moving past the ring seal.
One solution known in the art to keeping these radial friction forces to a minimum is to force the ring seal to move in an axial direction against a tab or groove formed on the stationary component. By using axial forces, radial forces can be kept to a minimum. Axial forces typically originate from a pressure differential of the fluid on each side of the ring seal. As the pressure differential changes from one side of the ring seal to the other, the ring seal is able to move from one position sealed against the stationary component to a second position sealed against the stationary component.
However, during the transition between positions, there can be leakage of the fluid around the seal. One solution known in the art is to provide a second ring between the ring seal and one of the components. While effective for its intended purpose, the second ring can increase the radial forces of the ring seal, thereby increasing friction between the ring seal and the rotating element. Moreover, the second ring increases assembly costs. Therefore, there is room in the art for a ring seal that minimizes fluid leakage across the seal during transition while simultaneously providing a construction that does not increase assembly costs.